Piaster foundation



Feb. 26, 1935. w. F. SCHULZ PLASTER FQUNDAT I ON Original Filed Jan. 17,1951 Re. 19,480l

F' .3 9 8 g .9 Lg L/AA'M AfA Mx xxxxfxxl Reissued Feb. 26, 1935 PATENTOFFICE PLASTER/ FOUNDATION Walter F. Schulz, Youngstown, Ohio, assignorto Truscon Steel Company, Youngstown, Ohio, a corporation of MichiganOriginal No. 1,915,336, dated June 27, 1933, Serial No. 509,509, January17, 1931. Application for reissue November 21, 1934, Serial No. 754,193

Claims.

. One of the principal objects of the present invention is to provide arelatively inexpensive form of structure of that type in which a,backing sheet and an overlying foraminous sheet are employed, with meansof a sufficiently effective character to secure the two together so asto permit their mounting on studding, rafters or other supports, andholding the two in associated relation until plaster has been appliedand has set.

A further object is to provide a structure of this character thateliminates the necessity of perforating the backing sheet with securingmeans, thereby obviating the places at which the moisture of the plastercan find access to the interior of the backing between the supports. Inother words the necessity of breaking a Waterproofed backing sheet atnumerous points is eliminated.

The structure also obviates another serious difflculty. In themanufacture of these plaster bases, the plaster holding element isusually of expanded metal, and expanded metal is not and cannot alwaysbe produced with exact accuracy without material trouble and expense.The consequence is that the meshes will vary in size and shape, andwhere the expanded metal and board are united by machinery and staplesare employed as the uniting agency, the lattice of the expanded metalwill not always come accurately into place by reason of the aforesaidvariations. In the present embodiment this serious difficulty isovercome and a structure can be produced by machinery, irrespective ofdiscrepancies that may appear in the members.

In the accompanying drawing:

Figure 1 is a view in elevation of a plaster base constructed inaccordance with the present invention.

Figures 2 and 3 are respectively sectional views on the lines 2-2 and3-3 of Figure 1.

Figure 4 is a detail View illustrating the preferred form of fasteningthe foundation in place on a support.

In the disclosure, a backing board is employed, preferably of corrugatedfibre or paper. As shown it consists of a backing sheet 5, a facingsheet 6, and an interposed corrugated core 7.

This board, or at least the outer sheet 6, is substantiallywaterproofed.

Over the outer face of the outer sheet 6 is located a lathing sheet 8,which is preferably, though not necessarily, of expanded metal. Theexpanded metal sheet 8 is secured to the backing sheet or board bystrips 9 which may be of fabric, cord or some suitable non-metallicmaterial, but preferably paper. These may be laid in any direction overthe metal fabric 8, andL inthe openings are pressed down as will beclear by reference to Figure 2, so that at intervals they are in contactwith the outer face of the outer 5 sheet 6, and these portionsv aresecured by suitable adhesive to said backing board.

It will be noted by reference to Figures 1 and 4 that each strip 9 isnarrower than the interstices or openings in the foraminous materialheld. It will also be noted by reference to Figure 3 that the strips 9where they pass over the joined portions of the zig-zag strips that formthe foraminous material are spaced from the facing sheet. As aconsequence of the narrow strips the plaster will flow into the openingsthat are crossed by the strips and can pass under the portions of thestrips and interlock with the portions of the foraminous sheet beneaththem. The strips therefore do not materially interfere with theessential interlocking or keying action between the plaster and theforaminous lathing sheet.

Preferably the strips are substantially waterproofed and the adhesive iswaterproof. Silica of soda has been found peculiarly effective for thepurpose, not only because of its Waterproof character, but because itdries quickly. Casein glue may be employed, and indeed it has beenfoundV that vegetable or animal glue or other adhesive can besatisfactorily utilized sincethe moisture of the plaster does not seemto pass readily between the adhering portions of the sheets, and theplaster will set before any separation can take place. More than that,the strips have really fullled their functions after the plaster hasbeen applied, for when it sets, experience has demonstrated that it willadhere to the backing sheet so as to be actually supported thereby.Moreover in the preferred use of the board the metal lathing is itselfpreferably fastened to the supports. Thus, as indicated in Figure 4,nails having large heads 10 are driven through the board into thestudding 11 and overlies the metal.

It will be seen that with this structure the surface of the backingsheet is unbroken by fasteners passing through it, except at thestudding where it is backed by the latter, and consequently there are soopenings by which moisture can gain access to the interior of thebacking sheet between its points of support. A structure of this kindmoreover can be readily manufactured either by hand or by machinery, anyvariation in the arrangement of the mesh of the metal lathing notaffecting the application of the securing strips 9,

V'departing from the spirit or sacricing any of the advantages of theinvention.

What I claim, is:

1. A plaster base comprising a substantially flat backing sheet, asubstantially at foraminous lathing sheet that lies flat against thebacking sheet, and spacedrstrips of material extending over the lathingsheet and adhesively applied to the backing sheet at the openings onthel lathing sheet and securing the lathing sheet to the backing sheet.

Y 2 A plaster base comprising a backing sheet, a sheet of foraminousmaterial located thereover, and means extending over the foraminousmaterial and adhesively applied to the outer face of the backing sheetat openings in the foraminous material, said means being narrower thansaid openings across which it passes and leaving said openings and thevmaterial bounding them exposed.

3. A plaster base comprising a backing sheet, a sheet of expanded metallocated thereover, and a uniting strip extending over the foraminousmaterial and adhesively applied to the outer face of the backing sheetat openings in the expanded metal sheet, said strip being narrower thanthe openings at which it is secured and leaving the material of theexpanded metal sheet beneath said strip exposed at the crossing points.

4. A plaster base comprising a backing sheet having its outer :facesubstantially Waterproofed, a, foraminous metal sheet located over thesaid face of the sheet, `and a plurality of flexible strips extendingover the foraminous sheet and having portions thereof in the openings ofthe sheet adhesively secured to the backing sheet.

5. A plaster base comprising a backing sheet having its outer facesubstantially Waterproofed, a foraminous metal sheet located over thesaid face of the sheet, and a pluralityof exible substantiallywaterproofed strips extending over the foraminous sheet and havingportions thereof in the openings of the sheet secured to theWaterproofed face of the backing sheet by substantial' ly waterproofedadhesive.

